Asymmetric Synthesis of 1,3-Diamines by Diastereoselective Reduction of Enantiopure <i>N</i>-<i>tert</i>-Butanesulfinylketimines: Unusual Directing Effects of the <i>ortho</i>-Substituent
Chiral, nonracemic 1,3-diamines were prepared in a highly diastereoselective reduction of diaryl N-tert-butanesulfinylketimines. Correlation between Facial selectivity of the reduction and E or Z geometry of the starting ketimines suggests involvement of a cyclic transition state for the reduction. The ortho-substituent controls the geometry of N-tert-butanesulfinylketimines in the solid state and provides additional stabilization of the cyclic transition state.
AN IMPROVED ASYMMETRIC SYNTHESIS OF ALPHA-BRANCHED CHIRAL AMINES
申请人:Piramal Pharma Limited
公开号:EP3781547A1
公开(公告)日:2021-02-24
AN IMPROVED ASYMMETRIC SYNTHESIS OF alpha-BRANCHED CHIRAL AMINES
申请人:PIRAMAL PHARMA LIMITED
公开号:US20210114977A1
公开(公告)日:2021-04-22
The present invention relates to an improved asymmetric synthesis of alpha-branched amines (hereafter referred to as the compound) and relative chiral amines (1″) or its pharmaceutically acceptable salt and derivatives. The process comprises an unusual substrate specific regioselective ortho lithiation of substituted arene compounds, followed by its highly diastereoselective addition to N-tert-butanesulfinylimines resulting in the selective formation of alpha-branched sulfinyl amine and chiral amine; which on subsequently removing the sulfinyl group provides corresponding alpha-branched amines or relative chiral amines (1″).
Diastereoselective addition of anisoles to <i>N-tert</i>-butanesulfinyl imines <i>via</i> four-membered lithium cycles
highly regio- and diastereo-selective ortho-lithiation/addition of anisoles to N-tert-butanesulfinyl imines resulting in the selective formation of chiral α-branched amines is described. This method is also efficient for highly regioselective benzylic lithiation of o-methylanisoles, followed by diastereoselectiveaddition to N-tert-butanesulfinyl imines.
[EN] AN IMPROVED ASYMMETRIC SYNTHESIS OF ALPHA-BRANCHED CHIRAL AMINES<br/>[FR] SYNTHÈSE ASYMÉTRIQUE AMÉLIORÉE D'AMINES CHIRALES ALPHA-RAMIFIÉES
申请人:PIRAMAL ENTPR LTD
公开号:WO2019202522A1
公开(公告)日:2019-10-24
The present invention relates to an improved asymmetric synthesis of alpha- branched amines (hereafter referred to as the compound (1)) and relative chiral amines (1'') or its pharmaceutically acceptable salt and derivatives. The process comprises an unusual substrate specific regioselective ortho lithiation of substituted arene compounds, followed by its highly diastereoselective addition to N-tert-butanesulfinylimines resulting in the selective formation of alpha-branched sulfinyl amine (4) and chiral amine (6); which on subsequently removing the sulfinyl group provides corresponding alpha-branched amines (1) or relative chiral amines (1'').